TECHNICAL TOOLS POWDER-COATING OF CERAMIC MATERIALS. Technique for the powder-coating of non-conductive materials. Information:

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1 TECHNICAL TOOLS Ideas and applications for GiColor products POWDER-COATING OF CERAMIC MATERIALS Technique for the powder-coating of non-conductive materials Information: 1. Versatility of powder coating 2. Technique for the powder coating of ceramic materials 3. Possible applications MRK

2 1. Versatility of powder-coatings Powder-coatings are designed for the application on conductive materials, but with a specific technique it is possible to use them also on non-conductive materials, such as ceramic and pottery, thus expanding the versatility of these products and the results that we can obtain. Pottery, suitable for the decoration with powder coating 2. Technique for the powder coating of pottery a) Preparation After preparation and careful cleaning, the sample is hung with a hook or firmly placed on a metal rod, so that we can move it and put it into the oven without touching it directly (Picture 1). If possible, we recommend to avoid an asymmetric contact of the metal hook (or rod) on the sample: this may cause, first a higher electrostatic attraction of the powder particles on some spots of the ceramic object, secondly a faster and easier melting of the powder due to the thermal conductivity of the metal support. This can be prevented by using supports made of non-conductive materials, and that can resist at temperatures higher than the curing temperature.

3 Picture 1: preparation of the sample on a hook, in order to move it without touching it b) Pre-heating The sample is put into the oven at 248 F C (melting temperature): in this way, during the following step of the powder coating technique (see c- Application ) the powder will stick to the object as it touches the hot surface, due to instantaneous melting. The whole ceramic sample must be hot: for this reason, the longer the object will remain in the oven, the easier and the better the subsequent application of the powder will result. Pre-heating also allows the expulsion of possible volatile compounds inside the material, that could generate defects after the application and during the curing of the powder. Approximately, pre-heating should take at least 15 minutes, but it can vary depending on shape and dimensions of the specific object.

4 c) Application We take the sample out of the oven and we immediately spray the powder on it (Picturese 2a, 2b, 2c, 2d). The application is carried out just as for normal (conductive) objects, but it will result easy and homogeneous as long as the sample is hot; for this reason it has to be done rapidly. The voltage can be set at 0 V, since the powder does not stick to the sample for electrostatic attraction. While spraying the powder, we ll observe its instant melting on the sample: it is normal, but for powders with special surface effects (Saltlake, Icetouch...) we ll observe the characteristic textured finish only at the end of the curing cycle. Pictures 2a, 2b, 2c, 2d: application of the powder on the hot pre-heated pottery Attention: in case of defects (due for example to dust fallen on the sample, or contact with other objects that spoil the layer of melt powder) it is not possible to remove the sprayed powder as in the case of normal application (on cold conductive objects). Every contact with the melt powder will compromise the perfection of the result.

5 d) Curing We put the sample into the oven for the time and temperatures reported on the TDS of the product used. Due to the low thermal conductivity of ceramic materials, complete curing could take longer than analogous metal samples (up to minutes more): curing conditions, indeed, always refer to the temperature of the sample. Picture 3: the sample inside the oven with its support, to complete the curing e) Cooling down The sample is carefully pulled out of the oven and let cool down to room temperature. Picture 4: the sample, coated with Rame-04

6 3. Possible applications Every ceramic object can be coated with this technique. Striking results can be obtained with pottery vases and round shapes that valorize the metallization and the opalescence of the powder coating products. Amazing solutions can also be obtained by choosing powders with special textured surface, like Icetouch or Saltlake, for original effects of color and light. Pottery coated with (left to right): Rame-04, Saltlake-025, 13M-126-A046

7 A close view of the pottery coated with 13M-126-A046 (left), and with Saltlake-025 (right) Earthenware frames: base (left), powder-coated with Sahara-02 (center), and with Artico-04 (right)

8 GICOLOR S.R.L. Sede legale: Viale del Lavoro, 5 - Arcole (VR) Sede operativa: via Tagliamento, Belvedere di Tezze sul brenta (VI) Italy Tel Fax